My DX58OG fails to boot every other time, literally every alternate boot fails with "C1" error and long-short-short beep. I'm having to power down, power it back up, and face the screen that asks you to "press Y to enter BIOS, press N to boot with previous settings".

Not even a single component (not the processor, not the memory, nothing) is overclocked. That's partly also because this board is fundamentally incapable of overclocking. Even 134 MHz base clock will fail to POST, forget using the XMP-1600 profile of my vastly popular Corsair XMS3 3x 2GB memory kit.

So despite running 100% virgin settings, this board fails every alternate boot. And yes, I've replaced the board once with the retailer, and yes, I've updated to the latest BIOS, and yes, I have a stable 700W power supply.

Also, the processor and memory have run in mint condition on a Gigabyte X58A-UD7 previously.

My friends literally begged me to pick the similarly priced ASUS X58 Sabertooth over the DX58OG, but I picked it anyway out of good faith in the Intel brand. I was wrong.

The I7-950 has a built in Memory controller that has limits of DDR3-800 to DDR3-10600. That may cause problems being as you have DDR3-1600. I would get the right ram or change the CPU so you can run the DDR3-1600 RAM.

No, every alternate boot with the default DDR3-1066 MHz fails. I already told you I'm not using that XMP-1600 profile. DDR3-1066 is the default memory standard of the Core i7-950 IMC, and my memory is more than capable of that.